OpenGL實現立體顯示

立體顯示原理：設沒有立體顯示的模型視圖矩陣ModelView爲Mv,投影矩陣爲Mp，則、物體空間的任何一點爲P，則變換到屏幕座標P*=Mp×Mv×P；注意前面已經說過opengl裏面座標列優先，所以矩陣都是右乘。

左眼和右眼的變換都是由中間的變換矩陣變換而來，則立體顯示中左眼的變換矩陣公式爲：

P(L)*=Ms(L) × Mp(L) × Mt(L) × Mv(L) × P；

右眼的矩陣變換公式爲：

P(R)*=Ms(R) × Mp(R) × Mt(R) × Mv(R) × P；

其中Ms，Mt是立體顯示需要而增加的變換。

程序裏面有幾個參數，現實世界眼睛到屏幕的距離Fd，兩眼之間的距離Sd，比例尺R，如圖：

如上圖：沒有立體顯示，視點位於就是中間的藍色位置，立體顯示就是將左眼(紅色)，右眼(綠色)的視圖分開繪製。

程序中左眼用紅色去畫，右眼同時用綠色和藍色繪製。

 

代碼：

/* * @(#)$Id: SteroShow.cpp [4/24/2008 RenYaFei] [e-mail] $ * @(#)基於OpenGL的立體顯示實現 * Author: Dizuo.Hangzhou. * All Rights Reserved. */ #include <GL/glut.h> #include <math.h> void init(void) { GLfloat mat_diffuse[] = { 1.0, 1.0, 0.0 }; GLfloat mat_specular[] = {0.8, 0.8, 0.0, 1.0}; GLfloat mat_shininess[] = { 300. }; GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 }; GLfloat light_diffuse[] = { 1.0, 1.0, 0.0 }; GLfloat light_ambient[] = {0.7, 0.2, 0.2, 1.0}; glClearColor (0.0, 0.0, 0.0, 0.0); glShadeModel (GL_SMOOTH); glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular); glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse); glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess); glLightfv(GL_LIGHT0, GL_POSITION, light_position); glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient); glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_DEPTH_TEST); } /**//*---------------------------------------------------------------------------- * 初始化參數 */ GLfloat PI=3.1415926; GLfloat Fd=5.0; //fusion distance GLfloat RealScreenToEyeDistance=1.0; GLfloat R=Fd/RealScreenToEyeDistance; //比例尺 R = Fd / RealScreenToEyeDistance GLfloat Sd=0.05; //兩眼之間的距離 GLfloat aspect=1.0; //gluLookAt函數裏面的參數 GLfloat fovy=60.0; //張角 GLfloat f=1/tan( (fovy*PI)/(2*180) ); //f=ctg(fovy/2); //列優先的矩陣模型視圖矩陣，投影矩陣 GLfloat LeftModelViewMatrix[16]={ 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, Sd*R/2.0, 0.0, 0.0, 1.0 }; GLfloat LeftProjectMatrix[16]={ 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, -(Sd*f) / (2.0*Fd*aspect), 0.0, 0.0, 1.0 }; GLfloat RightModelViewMatrix[16]={ 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, -Sd*R/2.0, 0.0, 0.0, 1.0 }; GLfloat RightProjectMatrix[16]={ 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, (Sd*f) / (2.0*Fd*aspect), 0.0, 0.0, 1.0 }; //for the use of rotating static GLfloat spin = 0.0; void display(void) { GLfloat matrix[16]={0.}; glColorMask(1.0, 1.0,1.0,1.0); glClearColor(0.0,0.0,0.0,1.0); glClearDepth(1.0); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glColor3f(1.0, 1.0, 1.0); //--------------------------------------------------------------------------------------------- //Left Viewport glMatrixMode(GL_PROJECTION); glPushMatrix(); glGetFloatv(GL_PROJECTION_MATRIX, matrix); glLoadIdentity(); glMultMatrixf(LeftProjectMatrix); glMultMatrixf(matrix); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslated(0.0, 0.0, -Fd); glPushMatrix(); { glGetFloatv(GL_MODELVIEW_MATRIX, matrix); glLoadIdentity(); glMultMatrixf(LeftModelViewMatrix); glMultMatrixf(matrix); glColorMask(1.0, 0.0, 0.0, 1.0); /**//* * 物體的座標Vp * 變換到屏幕座標：Vp'= LeftProjectMatrix×Mp × LeftModelViewMatrix×Mv × Mr×Vp */ glPushMatrix(); { glRotatef(spin, 0.0, 1.0, 0.0); glutSolidTeapot(1.0); } glPopMatrix(); } glPopMatrix(); glMatrixMode(GL_PROJECTION); glPopMatrix(); glFlush(); //--------------------------------------------------------------------------------------------- //Right Viewport glMatrixMode(GL_PROJECTION); glPushMatrix(); glGetFloatv(GL_PROJECTION_MATRIX, matrix); glLoadIdentity(); glMultMatrixf(RightProjectMatrix); glMultMatrixf(matrix); glMatrixMode(GL_MODELVIEW); glPushMatrix(); { glGetFloatv(GL_MODELVIEW_MATRIX, matrix); glLoadIdentity(); glMultMatrixf(RightModelViewMatrix); glMultMatrixf(matrix); glColorMask(0.0, 1.0, 1.0, 1.0); glClearDepth(1.0); glClear(GL_DEPTH_BUFFER_BIT); /**//* * 物體的座標Vp * 變換到屏幕座標：Vp'= RightProjectMatrix×Mp× RightModelViewMatrix×Mv × Mr×Vp */ glPushMatrix(); { glRotatef(spin, 0.0, 1.0, 0.0); glutSolidTeapot(1.0); //glutSolidSphere(1.0, 20, 5); } } glPopMatrix(); glMatrixMode(GL_PROJECTION); glPopMatrix(); glFlush (); glutSwapBuffers(); } void reshape (int w, int h) { glViewport (0, 0, (GLsizei) w, (GLsizei) h); glMatrixMode (GL_PROJECTION); glLoadIdentity(); //投影矩陣：Mp gluPerspective(fovy, (GLfloat)w/(GLfloat)h, 1.0, 20.0); } void spinDisplay(void) { spin = spin + 1.0; if (spin > 360.0) spin = spin - 360.0; glutPostRedisplay(); } int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); glutInitWindowSize (500, 500); glutInitWindowPosition (100, 100); glutCreateWindow (argv[0]); init (); glutDisplayFunc(display); glutReshapeFunc(reshape); glutIdleFunc(spinDisplay); glutMainLoop(); return 0; }

相關立體顯示鏈接：http://local.wasp.uwa.edu.au/~pbourke/projection/stereorender/